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Highly efficient kinetic resolution of 2 H-azirines by an asymmetric imine amidation was achieved in the presence of a chiral N, N′-dioxide/ScIII complex, thus providing a promising method to obtain the enantioenriched 2 H-azirine derivatives and protecting-group free aziridines at the same time. It is rare to find an example of N1 of an oxindole participating in a reaction over C3. Moreover, chiral 2 H-azirines were stereospecifically transformed into an unprotected aziridine and α-amino ketone. [ABSTRACT FROM AUTHOR]

The asymmetric propargyl Claisen rearrangement provides a convenient entry to chiral allene motifs. Herein, we describe the development of a kinetic resolution and asymmetric rearrangement of racemic propargyl vinyl ethers. This transformation afforded chiral allene products along with the enantiomerically enriched substrate in good yields with excellent diastereo- and enantioselectivity. The complete chirality transfer and facially selective rearrangement enabled the simultaneous construction of an axially chiral allenic unit and a quaternary carbon stereocenter. [ABSTRACT FROM AUTHOR]

A kinetic resolution of racemic 2-substitutedcyclopentanones viahighly regio- and enantioselective Baeyer–Villiger oxidationhas been successfully developed. The reaction could afford the normal6-substituted δ-lactones in up to 98% ee and >19/1 regioselectivity.Meanwhile, the unreacted ketones were recovered in excellent ee values(up to 98%). It represents the best results of the kinetic resolutionof racemic 2-substituted cyclopentanones via nonenzymic asymmetricBV oxidation. [ABSTRACT FROM AUTHOR]